The number of sites providing PCI without on-site cardiac surgery (no-SOS) has doubled from 2009 to 2021, now accounting for almost one-half of PCI-capable facilities in the U.S., and risk-adjusted in-hospital outcomes for PCI by SOS status were similar, according to a Brief Report published April 28 in JACC.

Using data from the ACC's CathPCI Registry, Javier A. Valle, MD, MSc, FACC, et al., explored the prevalence of no-SOS facilities over time and investigated the contemporary practice and clinical outcomes of PCI being performed at these sites. Patients undergoing PCI at no-SOS sites had a similar median age (no-SOS: 66 years vs. SOS: 67 years), higher female representation, and generally lower risk profiles with lower rates of comorbid conditions.

Overall, the number of no-SOS sites grew in the U.S. from 296 in 2009 to 715 in 2021, representing 43% of PCI-capable sites in 2021. Out of 304 hospital referral regions (HRRs), the majority had at least one no-SOS site, while the median number per HRR was two. There were 17 HRRs with at least 10 no-SOS sites.

After adjustment, mortality risk for patients undergoing PCI at no-SOS sites was lower (odds ratio [OR], 0.92; 95% CI, 0.87-0.97). There was no statistically significant difference in the odds of in-hospital stroke, bleeding and severe acute kidney injury (AKI) between groups. These results were largely consistent when stratified by indication (STEMI, NSTE-Acute Coronary Syndrome [ACS], non-ACS); however, ORs favored no-SOS sites for in-hospital bleeding in patients with STEMI and severe AKI in non-ACS patients.

The authors acknowledge specific study limitations, including its observational design, making residual confounding possible, and their evaluation of individual sites, removing them from the context of their larger health systems or regional referral systems.

"It is possible that these aggregate outcomes may not be representative of those found within 'hub and spoke' models," they write. "More dedicated evaluation and comparison of individual health care delivery models may be needed."